Insulator-knob.



J. W. HOME-R.

INSULATOH KNOB.

APPLICATION min rEa.24.1915.

1 ,21 8, 1 8 1 Patented Mar. 6, 19.17.

`JOI-IN W. HOMER, OF GREENCASTLE, ENNSYLVANIA.

INSULATOEKNOB.

Specification of Letters Patent.

Patented Mar. e, 1917.

Application filed February 24, 1915. Serial No. 10,313.

To all whom it may concern:

Be it known that I, JOHN W. HoMER, a citizen of the United States, residing -at Greencastle, in the county of Franklin and State of Pennsylvania, have invented certain new and useful Improvements in Insulater-Knobs; and VI do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which `1t appertains to make and use the same.

This invention relatesy to electric conductors, and more especially to insulators and the objects of the same are to improvethe devices heretofore used for holding together the two parts of a porcelain insulatorfor knob.

The improvement consists particularlyl in the employment of means for 'preventing contact of the nail or screw with the `porcelain at any point, under all ordinary conditions, and the provision of a cushionfover the head of the knob so that-when the `nail is driven home the impact of the blow will not crack' the head. yThe present invention possesses other. advantageous features which will appear from the following specification.

In the drawings: f l

Figure l is a sectional view of this invention'complete, and Fig. 2 is a bottom plan view of` the insulator with the' fiber washer indicated in dotted lines and showing how it centers the nail or screw within the bore of the insulator base.

Fig. 3 is a plan view of one of the fiber washers before it is applied, Fig. 4 shows its application to a nail, and Fig. 5 its application to a screw.

Fig. 6 is an enlarged sectional view through one Aof the -leather washers in place on'va screw.

Fig. 7 is a similar view of a slightly modified form of leather washer'with slits, and

'Fig'.S of another modification of the same.

In the drawings, the numeral l designates the top 0r cap member ofthe insulator knob, and 2 is the base member thereof, the

'latter being formed in its lowered end with a recess''preferably containing aseries of webs l whose lower edges incline upwardly andinwardly and preferably have shoulders 5 within their length. These two -members or portions of the insulator are usually made of glass, porcelain, or some friable material, and they are provided with alined bores 6 through which passes a nail 7 or a screw 8 which is of sufficient length to extend completely through both members so that its point may be engaged with the cross bar of the telegraph pole or the other support on which the insulator is to be mounted.

The numeral 9 designates the head of either the nail or the screw, and 10 is its point, the latter being reduced in the case of a nail and threaded for some distance upI the shank in the case of a screw. Means are commonly Aprovided such as a socket'll in one insula- `a box or pouch, perhaps a bag slung over his shoulderI by a strap; and on reaching the pointwhere one is to be used he climbs the pole to a cross bar and throws his arm over it or around the pole to support himself while at work, and obviously he has not the full and unhampered use of both his hands. Hence it is desirable that when he reaches for an insulator knob one hand can pick up both members of it and the nail which connects them and hold the whole in place while the other hand may drive the nail. I willi use the word nail to refer to either a nail or screw throughout this specification. Also on his way to work and throughout the day, his time is saved if means are present to keep the two members of every knob and its nail assembled. Therefore provision has heretofore been made for the use of a washer on the shank of the nail below the base member and which will co-act with the head of the nail to perform this duty. This washer is commonly made of paper or fiber and slipped onto the shank of the nail at the time the-parts are assembled. I lind, however, that the washer often slips off, either while the parts are in the boxl or perhaps at the moment the lineman is taking'out an insulator or about to drive its nail into the cross bar, and the result is considerable loss of time which it is one of the purposes of my invention to economize. Again, if the shank of the nail fits too closely in the bore of the members of the insulator, or the latter be shaken too vigorously, or perhaps dropped, the contact of metal with porcelain will often break one or both members. Finally, the impact of the hammer on the nail head 9 when the tip of the nail is driven home often breaks the cap member 1 or perhaps drives the projection 12 into the socket 11 and breaks the base member 2, again with loss of time and materials. It is therefore the specific object of the present invention to overcome these contingencies as far as possible.

By preference I make the shank of the nail 7 or screw 8 smaller than the bore G of the members. The paper or fiber washer which I will herein call a disk 2O is by preference made of such circumference that it rests on the webs 4 and its periphery fits against the shoulders 5, and the result is that it centers the nail within the bore so that it will take a considerable shock to throw porcelain into contact with metal. I also make use of a rather thick leather disk herein specified as a washer 30 as described below, which also may have means as shown in Fig. 7 for centering the upper end of the shank of a nail. The disk 20 while preferably thin, could be thicker than shown herein and could in fact be a duplicate of the Washer 30 as to size and material. But I )refer to make it of paper or liber, and at its center I cut through it a hole 21 which is slightly smaller than the shank 7 of the nail, and then through its body I cut a number of radial slits 22 as best seen in Fig. 3.

Vhen this washer is slipped over the point 10 of the nail the tongues 23 between said slits bend slightly as seen in Fig. fl, and their curved and blunted inner ends abut against the side of the shank. The result is that when au effort is made to move the latter in the other direction every tongue becomes a brace, its blunted inner end resting against the side of the shank, and the movement of said shank biting against said end rather than slipping past it in this direction so that the tendency is to push the entire tongue radially outward. rIhis action would not occur if it were not for the hole Q1; that is to say, if the tongues were strictly triangular their inner ends would be pointed and they would clasp the shank of the nail only by their resiliency. In the use of a screw as seen in Fig. 5, these blunted inner ends of the tongues drop into the grooves or threads, and if the size of the screw and the depth of its threads are in proper proportion to the size of the hole 21, the biting effect of the disk upon 'the screw is particularly strong.

The leather washer shown in Figs. G and 7 may have its body 30 made circular or in any other desired shape. It is preferably somewhat thicker than the disk, and I speak of it as leather because that is the material I prefer. It also may have a central hole 31 and radial slits 32, although in this case the hole might be made larger and the slits omitted. In Fig. 7 I have shown the edge of this washer as undercut at 35, and in Fig. S as stepped at 36, for the purpose of illustrating the fact that it could be so shaped as to enter the bore 6 of the cap member l and center the nail therein, rather than wholly overlying the upper end of said cap as seen in Fig. 1. I'Iere again the slits 32 could be employed. Or they might be omitted, as the position of this washer (except when it is used in place of the disk) dispenses with the necessity for the clinging action of the tongues on the nail; and even when it is used in place of the disk, its thickness and material will possibly give it suflicicnt cling.

My improved :insulator is assembled by first slipping a washer onto a nail or screw and moving it along the shank and into contact with the head 9 thereof, then applying the caps 1 and the base 2, and finally slipping a disk 2O over the point 10 and along the shank until its periphery rests upon the edges of the inclined webs 4 and fits into the shoulders 5 thereof if said shoulders are employed. The washer and disk now hold the man applies one of these insulators in the manner above outlined, he has but to pick it out of his box and put it in place with one hand, and then drive on the nail head with a hammer held in the other hand; and if his last blow in sinking the nail should be such as otherwise might cause the head 9 to crack the insulator cap, the presence of a soft washer 30 between these parts prevents that contingency. If a screw 8 be used instead of a nail, the same advantageous results are present.

lWhat I claim is:

1. AnV insulator formed of two members having alined bores, and the lowermost member having a recess in its lower end and radial webs within said recess with upwardly and inwardly inclined lower edges; combined with a. fastening device passing through said bores, and a washer on such device and resting on the edges of said webs.

2. An insulator formed of two members having alined bores, and the lowermost member having a recess in its lower end and radial webs within said recess provided with shoulders in their lower edges equidistant from the axial line of this member; combined with a fastening device passing through said bores, and a disk-shaped washer on the shank of said device with its periphery resting in said shoulders, for the purpose set forth.

3. An insulator formed in two members having alined bores, and means on the contiguous faces of said members for holding having alined bores, and means on the con-- tiguous faces of said members for holding said bores in registry; combined with a fastening device passing through and appreciably smaller than said bores and having a head at its upper end, a washer under said head7 a disk on the shank of said fastening device, and means for centering said disk and device with respect to the lower end of the bore and for holding it against said lower member.

5. An insulator formed in two members having alined bores, and means on the contiguous faces of said members for holding Said bores in registry; combined with a fastening device passing through and appreciably smaller than said bores and having a head at its upper end, and a washer under said head and reduced at its lower portion to enter the upper end of said bore, a disk on the shank of said fastening device, and means for centering said disk and device with respect to the lower end of the bore and for holding it against said lower member.

In testimony whereof I ai'lix my signature in presence of two witnesses.

JOHN W. HOMER.

Witnesses:

CHARLES F. HoMEa; THOMAS H. GILLAND.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

